Display devices are commonly used to display signals received from external electronic devices, in particular computing devices such as personal computers (PC). In particular, in office environments the display device itself or the computing device connected thereto are often left running for extensive periods of time, resulting in an unnecessary consumption of electrical energy. While the energy consumption of the individual devices has been decreasing due to advances in technology such as the widespread use of liquid crystal displays (LCD) rather than conventional cathode ray tubes (CRT), the ever increasing use of information technology (IT) still results in a considerable waste of electrical energy.
In this context, various solutions aimed at reducing power consumption of computing devices and display devices have been developed. In particular, most modern operating systems (OS) provide some form of energy management. Known operating systems, for example, the Microsoft Windows operating system family can usually be configured to send predetermined devices into an energy saving mode if a user ceases to perform input operations such as typing via a keyboard or handling a pointing device such as a computer mouse. In response thereto, components like hard disk drives (HDD) of the computing device can be deactivated or the processor can be switched into a standby mode, for example.
With regard to display devices in particular, the so-called Display Power Management Signaling (DPMS) standard of the Video Electronics Standards Association (VESA) provides a mechanism of switching a display device into a power saving mode. According to VESA DPMS, the display device can be switched into a standby mode, for example, by deactivating synchronization or similar control systems transmitted from the computing device to the display device. In response, the display device may deactivate a display screen or other electronic components.
While the described approaches have improved the energy efficiency of computer systems in general, they are not always effective. For example, a user needs to provide certain timeout periods for the deactivation of particular functions of a computer system. If the selected timeout period is too short, the user will be inconvenienced by the unexpected deactivation of parts of the computer system during relatively short input breaks. If the timeout period is too long, the energy efficiency of the computer system will be reduced by keeping its components in an operating state too long.
EP 2 000 881 A1 describes a computing system having an integrated display and an integrated energy management device. The electronic device further comprises a sensor indicating whether a user is present in front of the electronic device. In case the user is present in front of the electronic device, activation of a predetermined energy saving mode by the operating system can be prevented. Consequently, relatively short timeout periods for the activation of energy saving modes can be specified without inconveniencing the user.
While the described system has many advantages regarding energy efficiency of integrated computing devices, it is not applicable to computing devices without an internal sensor. Furthermore, the proposed solution still heavily depends on the proper configuration of an energy management system of the operating system of the computing device.
Therefore, it could be helpful to provide an alternative approach to managing the operating states of a computer system comprising at least one display device and at least one computing device connected thereto.